Remnant Geometric Hall Response in a Quantum Quench.

  title={Remnant Geometric Hall Response in a Quantum Quench.},
  author={Justin H. Wilson and Justin C. W. Song and Gil Refael},
  journal={Physical review letters},
  volume={117 23},
Out-of-equilibrium systems can host phenomena that transcend the usual restrictions of equilibrium systems. Here, we unveil how out-of-equilibrium states, prepared via a quantum quench in a two-band system, can exhibit a nonzero Hall-type current-a remnant Hall response-even when the instantaneous Hamiltonian is time reversal symmetric (in contrast to equilibrium Hall currents). Interestingly, the remnant Hall response arises from the coherent dynamics of the wave function that retain a remnant… 

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